Inventories (Schedule of Inventory) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Finished goods	$ 126.4	$ 128.8
Work in process	24.1	27.5
Raw materials, supplies and other	260.4	232.0
Inventories	$ 410.9	$ 388.3

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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